Jack



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comentaris r. ennemi, or new vor;

, N. Y., SSIGNOR 0F @NE-Alli? TO' NATHAN i GlUlINSlElURGt, F NEW WOM, lll'. Y.

JMC.

application nlerl'luly 30,

'llhis invention relates to jacks, and has particular reference to an improvement in fluid operated jacks.

'lhe invention primarily comprehends a jack including a plurality of telescopically associated tubular sections, the outer-most sections of which are closed at the outer ends, together with means for normally collapsing the sections into a nested closed relation, with means for introducing Huid under pressure. to the interior of the sections. for distending the jack. j

'lhe invention furthermore comprehends a jack of the character set forth including a head and a base section the former co-acting with the latter to seal the sections when closed againstthe entrance of dust, dirt or other foreign'matter.

As a further object the invention comprehends a jack of the character set forth including a coiled contractile spring having swiveled connection in its opposite ends with the closed ends of the head and base sections whereby to permit of the screwing or unscrewing of the end Walls to facilitate the assembly or disassembly of the jack.

'llhe invention furthermore embodies means on the base and intermediate sections for limiting the movement of the same to a collapsed position whereby to prevent obstruction to the introduction or exhaust of the Huid pressure to the interior of the jack structure.

its a still further object the invention comprehends a common Huid inlet and exhaust for the jack.

'llhe invention furthermore aims to provide a Huid operated jack which is comparatively simple in its construction, inexpensive to manufacture, and which is thoroughly reliable and highly ecient in its purpose.

With the above recited and other objects in view, reference is had to the following specification and accompanying drawings in which there is exhibited one example or embodiment of the invention, which is in no way intended as a limitation upon the scope of the appended claim as it is to be clearly understood that variations and modifications which properly fall within the scope of said claims may be resorted to when found expedient.

ln the drawings,

Figure 1 is a vertical sectional view through the jack in fully distended position;

lligure 2 is a sectional view therethrough 19%6. Serial No. 126,036.

taken approximately on the line 2-2 in Figure 1;

Figure 3 is a vertical sectional view through the jack in fully closed or collapsed position.

Referring to the drawings by characters of reference the jack includes a base section 5, one or more intermediate sections 6, and a head section 7, each of which sections are of substantially tubular formation. rllhe lowermost or base section 5 is closed atits lower end by a member 8 which is detachably connected to the lower section 5 in any suitable manner, such as by engaging the threaded boss 9 with the exteriorly threaded lower end of section 5. '-lhe base section 5 is further providedv at its upper end with an annular flange 10 on its exterior periphery, which flange is of a diameter to snugly tit the inner diameter of the next adjacent upper section G. The intermediate section or sections 6 are provided respectively at the lower and upper ends with inwardly and outwardly projecting peripheral flanges 11 and 12. The former adapted to snugly titthe external diameter of the next adjacent lower section, and the latter of an appropriate diameter to lit within the next adjacent upper section. The head section 7 is closed at its upper end by a cap 13 which is detachablyl associated therewith in any suitable manner such as by threadedly engaging a depending threaded boss 14 with the upper exteriorly threaded end of section. rl`he said head section l is formed adjacent its lower end with an inwardly projecting flange 15 of an internal diameter which is adapted to snugly fit the external diameter of the next adjacent lower section. All of the flanges 10,11, 12 and 15 are preferably formed with packing rings 16 to seal the structure against the escape of fluid while permitting of relative axial or telescopic movement of the sections. ln order to limit the inward movement of the intermediate and base sections to a collapsed or closed relation so as to space the upper ends of said sections from the underside of the cap 13, a plurality of circumfcrentially spaced upwardly rejecting stock pins 17 are provided on the upper end of each of the intermediate and base sections. At a point between the upward limit of movement of the upper ends of the base and intermediate sections a conduit 18 extends through the section 7 and connects with the interior of the jack. The conduit 1.8 at its opposite end communicates with one port 19 of a threelOlli way valve 20 which valve is further provided with inlet and exhaust ports 21 and 22. The inlet port 21 connects with a suitable conduit 23 which leads from a source of fluid supply such as compressed air, while the exhaust port 22 connects with an exhaust conduit 24. A rotary valve core 25 having a substantial T-shaped passage 26 is moveable respectively to positions for establishing communication between the ports 21 and 19 or 22 and 19, or an intermediate neutral position where the ports 19, 21 and 22 are all out of communication. A coiled contractile spring 27 is arranged Within the jack structure and has its opposite extremities 28 and 29 attached to the member 8 and cap 13 by swiveled bearing elements 30 and 31 whereby the spring normally tends to collapse or close the sections to the nested relation illustrated in Figure 3. The swiveled bearing elements permit of the threading and unthreading of the member 8 and cap 13 without twisting the spring convolutions so that the assembly and disassembly of the jack structure is facilitated. It will be noted that the uppermost or headhsection 7 is formed with a depending lower end 32 which extended below the flange 15, and the upper face of the base member 8 is formed with a groove 33 for receiving the depending end 32 when the jack is in a collapsed or closed condition as illustrated in Figure 3 whereby the jack sections are sealed against the entrance of dust, dirt or other foreign matter.

In use, in operation assuming the j ack to be in the position illustrated in Figure 3,1the tl1ree-way valve is manipulated to admit air or other fluid under pressure from a source of supply to the interior of the jack. The pressure operates to effect a relative opening or distention of the telescopic sections against the action of the spring 27 and it is obvious that sufficient pressure may be introduced to effect any relative separation of the sections necessary for the particular work to be accomplished. When it is desired to collapse the jack the threeAvay valve is manipulated to dispose the core 25 in a position to establish communication between the ports 19 and 22 to allow the internal pressure to be exhausted so that the spring will function to collapse and nest the sections in their normal position.

lVhat is claimed is:

A jack including a plurality of telescopically associated tubular sections, the outermost sections having closed outer ends, and means for introducing fluid pressure to and exhausting the same from the interior of the sections for distending the jack and permitting of the collapsing thereof, the outer closed end of one outer section having a projecting flange formed with an annular groove and the innermost end of the other outer section having a projecting end ada ted to engage wit-hin the groove for sealing the 'working peripheries of the jack sections against the collection of dust, dirt, grit, or other foreign matter.

CORNELIUS F. GUERIN. 

